Platfokjff-balance



2 Sheets-Sheet 1 RQL. McCOLLUM.

Balance Scales.

No.1,048. Patented Dec. 31, 1838.

2 Sh t-Sh t2. R. L. McCOLLUM. 8e

Balance Scales.

No. 1,048. Patented Dec. 31, 1838.

ROBERT L. MCGOLLUM, OF

ROCHESTER, NEYV YORK.

PLATFORM-BALANCE.

Specification of Letters Patent No.

To all whom it may concern Be it known that 1, ROBERT L. MoCoL- non, ofthe city of Rochester, in the State of New York, have invented a new andimproved mode of employing the lever for the purpose of weighingponderous bodies, in a combination which I denominate the platformbalance, of which I declare the following to be a full and correctdescription, reference being had to the drawings accompanying thisspecification.

The machinery is contained in a rectangular box of wood which isrepresented in Drawing No. 1, the lid or platform being removed.

N, N are notches of cast-steel screwed to the bottom of the box, onwhich rest the edges which are the fulcra of the system of levers. Oneof these notches, of which there are four (one near each corner of thebox) is also represented by N in Drawing No. 3.

From one side of the box a spout projects, into which is inserted avertical pipe, or hollow pillar of wood of a square form. The index barrepresented in Drawing No. 1 turns upon edges which rest on platesscrewed to the sides of the pillar. An iron rod one end of which ishooked to the index bar and the other to the anterior extremity of thepole of the posterior lever hereinafter described, passes down throughthe pillar. The index bar and the iron rod are represented in DrawingNo. 3, Figure 1.

Drawing No. 2 represents the platform, or lid of the box, on which reststhe body whose weight is to be determined. It is represented reversed,the lower surface being exposed.

G, G, G, G are the feet, rectangular prisms of iron, which rest upon thetop of rings suspended from edges inserted into the f'evers. The feetare inserted into the platform at right angles to its plane.

Fig. 2, Drawing No. 3, represents the two levers, each consisting whenof iron of a single casting, including the arms.

A A A. A are the edges upon-which the levers turn and which rest uponthe notches (N N in Drawing No. 1) hereinbefore mentioned. Inside ofthese edges (that is nearer the center of the system) are four 1,048,dated December 31, 1838.

other edges B B B B, two upon each lever. Upon the latter edges hanground rings of cast iron which move freely upon the edges. Upon the topof these rings rest the feet of the platform.

The posterior lever (that is the one remote from the pillar whichsupports the index bar) has two arms converging together at somethingless than half the distance to the anterior lever, and uniting in asingle arm or pole, at the extremity of which is attached by a hook theiron rod connecting the system with the index or steelyard bar. Theanterior lever has two arms converging toward the pole of the posteriorlever. The extremities of these arms rest on the top of rings suspendedfrom edges inserted on each side of the pole of the posterior lever. Thearms it will be perceived are in fact the levers constituting fourlevers so constructed as to act as two.

The mode of operation is sufficiently obvious. The weight upon theplatform pressing down upon B B on the anterior lever, depresses theextremities of its arms which extremities press down upon the ringssuspended from the sides of the pole of the posterior lever, thus actingin conjunction with the direct pressure of the weight at B B on theposterior lever depressing the anterior extremity of its pole, whichpasses through an opening in the side of the box, represented in DrawingNo. 1, until it reaches the iron rod, through which it acts upon theindex bar.

hat I claim as my invention and desire to secure by Letters Patent isThe resting the feet of the platform upon the tops of rings suspendedupon edges and moving with perfect freedom upon them, so that the ringwill always adjust itself in such a manner that the bearing of theplatform shall be directly over the edge, and a similar adjustment ofthe other bearing points of the machinery of the balance all as abovedescribed.

ROBERT L. MOOOLLUM.

'Witnesses i E. PESHINE SMITH, P. G. BUoHAN.

